1. Field of the Invention
The present invention relates to furniture constructed from logs. More particularly, the present invention relates to a process for treating logs so as to prevent cracking
2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 37 CFR 1.98.
The use of logs to construct furniture is well known. As with the use of logs to create log homes, the use of logs in furniture is appealing both structurally and aesthetically. Throughout the world, many vendors sell articles of furniture constructed from logs of various types of woods. Log furniture can take the form of almost any type of furniture, from bedroom furniture sets to pool tables. Additionally, log furniture can be well suited for outdoor use, such as in patio furniture sets. Log furniture is often constructed by drilling a series of bolt holes through the logs. A series of bolts are threaded through the bolt holes and secured by nuts.
The use of various types of cedar logs to construct furniture is very common. White cedar, in particular, is preferred because it is very durable and naturally bacterial and fungal resistant. Cedar gives off organic compounds known as thujaplicins which contribute to the decay resistance. In addition, these organic compounds are responsible for the pleasant aroma of cedar and at the same time deter insects, moths and other pests. These properties also make cedar an appealing choice for products such as linen storage chests (“cedar chests”) and shoe trees.
Over time, cedar logs undergo a natural process known as checking. During this process, moisture is released from the wood and longitudinal cracks form along the log. These cracks form across the annual growth rings of the logs but do not go through the center, or heart, of the log. While these cracks do not significantly affect the structural integrity of the logs, they are easily visible and make the furniture less aesthetically pleasing to some. Cracking can also occur as logs are subjected to the elements. Moisture from rain causes the logs to swell, and as they dry moisture is released and additional cracking can occur.
Although the integrity of the logs may not significantly be affected by checking or cracking, the integrity of furniture made from the logs may be. When cracks form in log furniture after the furniture has been assembled, they may interfere with the system of bolts used to secure the furniture together. If a crack encounters a bolt hole, it may cause the bolt to loosen. When the bolts loosen, the furniture, such as a chair, may become wobbly or collapse altogether.
Naturally, human beings and other animals tend to avoid placing themselves in situations where they feel their balance is compromised. For example, a patron in a restaurant will immediately want to switch chairs if the one they sit in is wobbly. Whether or not the patron fears that the chair will collapse under their weight is irrelevant. The wobbly chair is deemed unsuitable for its purpose. The same is true in the case of log furniture. If a piece of log furniture becomes wobbly, the consumer will become dissatisfied and feel the need to repair or replace the furniture even if it is not actually in danger of collapsing. The furniture can become wobbly due to the natural checking or due to cracking caused by exposure to the elements.
There are various methods for treating wood or lumber that are well known and commonly used in the industry. The goals of these treatments are to increase the durability of the wood and also to protect it from insects and fungus. Chemical preservatives are applied to the wood, often using pressure processes. These chemicals, in their concentrated forms, are often classified as toxic. Many of these chemicals are not readily available to the public and may require special permitting and approval for use. Some chemical preservatives, such as coal-tar creosote, may be brushed onto the wood. While modern treatment methods are relatively environmentally friendly, decades of wood treatment using older methods have contaminated ground water and soil with chemicals such as arsenic.
Many patents have issued which describe complex treatment processes for wood. For example, U.S. Pat. No. 3,968,276, issued on Jul. 6, 1976 to Allen, describes a process for the treatment of wood to impregnate the wood fully to its core with a resin component system, simultaneously with or without a flame retarding agent or preservative. The process involves enclosing the wood in a chamber, evacuating the chamber in a slow time cycle, adding a prepolymer aqueous solution to submerge the wood, continuing the vacuum, securing the vacuum, and applying pressure of prepolymer solution until the wood reaches the refusal point. In certain more dense woods, the vacuum and pressure cycles are repeated. The chemicals are purged and the chamber is evacuated. A final vacuum removes the residual surface liquids.
U.S. Pat. No. 5,075,131, issued on Dec. 24, 1991 to Hattori et al., teaches a method for preservation treatment of wood which comprises the steps of radiating a laser beam on a part of the surface of the wood at the least to form small holes therein, impregnating the wood with a preservative, and then applying high frequency waves to the wood to dry it by dielectric heating.
U.S. Pat. No. 5,943,789, issued on Aug. 31, 1999 to Yamamoto, describes an apparatus for treating green wood for the purpose of creating lumber of suitable quality for building construction. The wood is placed in a treatment chamber with a sealed atmosphere, the temperature of the chamber is increased, and the wood is maintained at a specific temperature and humidity for a given period of time, the wood is then sprayed with hot water until the moisture content of the wood decreases to a desired level.
Various patents have issued relating to the treatment of wood, specifically logs. For example, U.S. Pat. No. 4,233,753, issued on Nov. 18, 1980 to Olson, describes a method for treating whole logs to prevent them from splitting as they are dried to a desired moisture content. Whole green logs are placed in a pressure vessel which is sealed. Preferably the logs are debarked before they are placed in the vessel, but they may be debarked after their removal therefrom. Steam is thereafter injected into the vessel until the wood throughout the logs has reached a temperature within the range of about 190 to 240° Fahrenheit, while condensed water and other fluids from the wood are drained from the vessel. Subsequently the pressure in the vessel is released at a rate slow enough that no significant collapse of the wood within the logs occurs, and when the logs are cool enough to handle they are removed, debarked if necessary, and dried in a room whose relative humidity is maintained not less than about 45% until the logs have reached a predetermined moisture content.
U.S. Pat. No. 4,443,990, issued on Apr. 24, 1984 to Johnson, teaches a method of processing and producing crack free logs by making a saw cut along opposite longitudinal side portions of a log immediately after harvesting and thus curing the log, without debarking, in a shaded, ventilated air space so that any cracks will be concentrated along the saw cuts. When a finished appearance is desired, a groove is formed along the opposite side portions of the log in registry with the saw cuts and a spline or strip of wood is inserted in each groove so that it projects beyond the periphery of the leg with the spline or strip being secured in the grooves by glueing or the like. The peripheral or exterior portion of the spline or strips is peeled or cut off so that the resulting surface is contiguous with the peripheral surface of the log.
A typical manufacturer of log furniture may be a small company or a single craftsman with limited resources. Therefore, a need has developed for a process for treating logs used in furniture which does not require expensive tools or systems such as pressure vessels and controlled humidity chambers as found in the prior art. Additionally, there is a need for a treatment process which does not require many chemicals which may be harmful to the environment or which are not readily available to the public.
It is an object of the present invention to provide a log treatment process which makes logs crack-resistant.
It is another object of the present invention to provide a log treatment process which makes logs resistant to mildew, mold and weather stains.
It is another object of the present invention to provide a log treatment process which requires a minimal amount of special tools or machines.
It is still another object of the present invention to provide a log treatment process which uses a limited amount of chemicals.
It is a further object of the present invention to provide a log treatment process which is economically feasible for smaller manufacturers.
It is still a further object of the present invention to provide a log treatment process whereby the furniture constructed with the logs does not become wobbly.
These and other objects and advantages of the present invention will become apparent from a reading of the attached specification and appended claims